Current Understanding and Challenges of Metal‐Doped MOFs for Photocatalytic Hydrogen Production

Semiconductor photocatalysts for solar hydrogen production face efficiency limitations from wide bandgaps and poor charge transfer. Metal–organic frameworks (MOFs) exhibit unique photocatalytic advantages through their porous architectures, ultrahigh surface areas, and tunable ligand structures. These features enable enhanced reactant interaction, tunable active sites, and extended light harvesting. The metal ion doping strategy represents a promising approach to further enhance the hydrogen production activity and stability of MOF photocatalysts. The incorporation of metal species can extend the light absorption range, serve as additional active sites and electron traps, effectively promote the separation and migration of photogenerated charge carriers, and suppress their recombination rate. This review focuses on recent research progress in metal ion‐doped MOFs photocatalysts. Based on the distinct metal doping strategies, the discussion is organized into substitution and incorporation sections. The hydrogen evolution activity, stability, and catalytic mechanisms of these materials are systematically analyzed and summarized. Finally, potential solutions to current challenges and future research prospects for metal ion‐doped MOFs photocatalysts are presented.